docs: def get_application_access_token(application_id, application_secret_key, api_version=None):
      """
      Get an OAuth access token for the given application.
  
      :param application_id: An integer describing a Facebook application's ID.
      :param application_secret_key: A string describing a Facebook application's secret key.
      """
      graph = GraphAPI(version=api_version)
  
      response = graph.get(
          path='oauth/access_token',
          client_id=application_id,
          client_secret=application_secret_key,
          grant_type='client_credentials'
      )
  
      try:
          data = parse_qs(response)
  
          try:
              return data['access_token'][0]
          except KeyError:
              raise GraphAPI.FacebookError('No access token given')
      except AttributeError:  # api_version >= 2.3 returns a dict
          return response['access_token'], None